An employee performing duties subject to more than one DOT Agency’s regulations must be randomly tested at the percentage rate established for the calendar year by the DOT Agency regulating more than 50 percent of the employee’s safety-sensitive functions. [See 49 CFR 382.305(n).] So, if you have an employee who drives your trucks 75 percent of the time and operates your transit buses 25 percent of the time, that employee needs to be in the FMCSA-regulated pool. All other testing (e.g., pre-employment, post-accident, reasonable suspicion) is regulated under the Agency that regulates the function the employee was performing at the time of the event. If an employee is involved in a crash while operating a transit bus, the employee is subject to post-accident testing under FTA regulations even if the employee is in the FMCSA random pool.